ovirt-reports: Dashboard results an error, when reports is not deployed

Reports tab shows error page when accessed after a server restart
before the reports web app has been deployed

A new Status servlet has been added to Reports app which is
used by the webadmin to check the status of the report webapp
before showing the reports web app in reports tab

Change-Id: I13d0345962226d383f1d795174b6a98089f35e7b
Bug-Url: https://bugzilla.redhat.com/1037667
Signed-off-by: Ravi Nori <rnori@redhat.com>